The rise of AI shopping agents is posing an awkward question for Amazon and Walmart: how do you let an AI assistant shop on your website without giving away the advertising revenue and customer data that make that website so profitable?
Reuters reported on November 4, 2026 that the two retailers are also the world’s two largest retail-media businesses, dominating an estimated $74.4 billion in US retail-media spending with a combined 88% share, according to projections from data firm Emarketer. AI-powered agents that research and buy products on a shopper’s behalf — such as Meta’s Muse — could erode the business of brands paying retailers to promote products on their websites and apps.
Morgan Stanley researchers said in July that such agents could account for 10% to 20% of US e-commerce spending by 2030. That is a projection, not a current fact, but it explains why the stakes feel so high: if shoppers increasingly buy through an agent rather than browsing a retailer’s own pages, the sponsored listings and product placements brands pay for may matter less.
Two opposite strategies
Amazon and Walmart have taken very different approaches to the same threat. Amazon blocked Meta’s Muse from its website in September, saying it appeared to have accessed its online store without authorisation, capturing and storing customer credentials. Meta declined to comment to Reuters. Amazon also won a court order blocking Perplexity’s shopping agent Comet in March, although the 9th US Circuit Court of Appeals overturned the ban in August.
Walmart, by contrast, rolled out infrastructure on October 21 to enable third-party agentic commerce, including Agent Profiles and a Walmart Agent Gateway that let approved AI assistants search products and complete purchases under customer-set controls. AFP reported that customers can require approval for every purchase or let an agent buy on its own up to a spending limit, such as $50, $100 or $200, and that agents do not receive customers’ payment card information.
The split is about more than technology. Walmart wants the sale wherever it starts; Amazon wants to protect the store, the data and the advertising inside it.
Why the ad business is so valuable
Retail media works because shoppers arrive ready to buy. Brands pay to be seen at the moment of purchase, and for Amazon and Walmart that has become a highly profitable sideline to selling goods. Amazon’s advertising revenue grew 11% year over year in the third quarter, Reuters reported, but that was its slowest pace of growth in nearly four years, according to LSEG data. Amazon chief executive Andy Jassy said last week that there is no meaningful effect yet on Amazon ads from third-party agents.
At Walmart, chief financial officer John David Rainey told analysts and investors in August that advertising, including the Walmart Connect retail-media business, along with membership and marketplace operations, accounted for 45% of quarterly operating income growth. Both companies are also testing ads inside their own AI assistants — Walmart within Sparky, its AI shopping chatbot, and Amazon within Alexa for Shopping — a sign they expect advertising to follow the shopper, even if the shopper arrives via an agent.
Emarketer forecasts that brands will spend 22.6% more on retail media in 2026 than last year’s $60.7 billion, so the prize is still growing even as the way people shop changes.
What it means for shoppers and brands
For shoppers, the near-term effect is mostly about choice and control: Walmart’s model lets an agent shop with spending limits and approvals, while Amazon’s model keeps shopping inside Amazon’s own tools. For brands, the risk is that an agent that picks a product on price, reviews or past purchases could bypass the sponsored placement they paid for.
Neither outcome is settled. Agents are still a small share of shopping today, Jassy’s comment suggests the ad impact so far is limited, and regulators and courts are still shaping what agents are allowed to do on other companies’ sites. What Reuters’ report makes clear is that the fight over AI shopping is not only about convenience — it is about who controls the moment a shopper decides to buy, and who gets paid for it.
Frequently asked questions
What is a retail-media business? It is advertising sold by a retailer on its own website and app, where brands pay to promote products to shoppers who are ready to buy.
How big is US retail media? Emarketer projects about $74.4 billion in US retail-media spending, with Amazon and Walmart holding a combined 88% share, according to Reuters.
How much shopping could AI agents handle? Morgan Stanley researchers said in July that agents could account for 10% to 20% of US e-commerce spending by 2030 — a projection, not a current figure.
Why did Amazon block Muse while Walmart welcomed agents? Amazon said Muse appeared to access its store without authorisation; Walmart chose to enable third-party agents through its Agent Gateway with customer controls such as spending limits and purchase approvals.
Sources:
- Reuters, “AI shopping agents could threaten Amazon and Walmart’s ad business”, November 4, 2026: https://www.reuters.com/business/media-telecom/ai-shopping-agents-could-threaten-amazon-walmarts-ad-business-2026-11-04/
- AFP via TechXplore, “Walmart welcomes AI agents as Anthropic launches its own”, October 22, 2026: https://techxplore.com/news/2026-10-walmart-ai-agents-anthropic.html
- The Hindu BusinessLine, “Walmart launches AI shopping tools for ChatGPT, Gemini and other agents”, October 22, 2026: https://www.thehindubusinessline.com/news/world/walmart-launches-ai-tools-to-let-agents-shop-and-complete-purchases/article71609558.ece
